Anode for cathodic protection of guy rods and anchors



D. c. HUBBARD 2,851,414 ANODE FOR CATHODIC PROTECTION OF GUY RODS AND ANCHORS Sgpt. 9, 1958 2 Sheets-Sheet 1 Filed May 3, 1954 IN VEN TOR.

ANCHORS 2 SheetsSheet 2 06W C INVENTOR Sept. 9, 1958 D. c. HUBBARD ANODE FOR CATHODIC PROTECTION OF GUY RODS AND Filed May 3, 1954 United States Patent fifice ANODE FOR CATHODIC PROTECTION OF GUY RODS AND AN CHORS David C. Hubbard, Centralia, Mo., assignor to A. B. Chance Company, Centralia, Mo., a corporation of Missouri Application May 3, 1954, Serial No. 427,140 2 Claims. (Cl. 204-197) improved protecting anodes for use with guy rods and anchors.

filed September 25, 1951, having the same this application is filed as a continuation-in-part for my prior application, which is being abandoned in favor of this application.

One of the objects of the present invention is the provision of improved methods and apparatus for protecting anchors and guy rods against corrosion which is due to cathodic action.

Another object of the invention is the provision of an improved form of installation of a protective anode in connection with a guy rod and, an anchor which protects the guy rod and anchor substantially against corrosion which may be due to galvanic action, until the anode has been consumed by such action.

Another object of the invention is the provision of an improved anode structure for protecting guy rods and anchors, which is simple in construction, which requires a minimum amount of machining, which is tightly attached to the guy rod and anchor assembly, and which will protect the assembly against corrosion for a long period of time without necessity for renewal of the anode.

Another object of the invention is the provision of an improved mode of installation and apparatus for protecting guy rods and anchors against corrosion, which does not involve the digging of a separate hole for an anode, and in which the anode and anchor and the guy rod can be installed as a unit, without the necessity for an interconnecting conductor.

Another object of the invention is the provision of a plurality of forms of eflicient anodes, which may be locked on the end of the guy rod in such manner that they will stay permanently assembled with the guy rod.

Another object is the provision of a modified form of installation in which the guy rod and guy cable are grounded and a closed circuit is provided which is completed through the earth.

Another object of the invention is the provision of an improved form of anode which provides a minimum amount of external surface for a maximum volume of magnesium, and in which the best current distribution is obtained and longest life of the anchor and guy rod accomplished.

Other objects and advantages of the invention will be apparent from the following description and the accompanying drawings in which similar characters of reference indicate similar parts throughout the several views.

Referring to the two sheets of drawings accompanying the specification,

Fig. l is a side elevational view in partial section, showing a guy rod and anchor installation provided with an anode embodying the invention Patented Sept. 9, 1958 Fig. 2 is a fragmentary sectional View, showing the details of construction of the anode when made of tubular stock;

Fig. 3 is a fragmentary sectional view, showing the details of construction of the anode when made of solid stock;

Fig. 4 is a third fragmentary sectional view, the construction of the anode when made of plate material;

Fig. 5 is a view similar to Fig. 1, showing another form of installation;

Fig. 6 is a view similar to Fig. 2 of a modified form of magnesium anode which has a maximum exterior surface for a minimum volume;

Fig. 7 is a view in perspective, showing a nut lock of the type illustrated at 17 and 18 in Fig. 1.

Referring to Fig. l, 10 indicates the guy rod, which is provided with a suitable eye structure 11 and with a threaded end portion 12 for receiving a nut 13, which constitutes a shoulder engaging the lower side of the earth anchor and resisting the pull of the guy rod.

For use with the present invention the threaded portion 12 is preferably made long enough to receive not only the nut 13, but the anode 14. The guy rod 10 is illustrated as passing through a central aperture 15 in an expanding steel anchor 16; and the nut 13 is located on the guy rod 10 and is located inside a nut retainer 1'7, comprising flanges, which engage the nut and prevent its rotation, and inwardly turned portions 18, which prevent the anchor 16 from sliding upward on the guy rod 10.

The present anchor installation is merely exemplary; and the present anodes may guy rods and anchors, provided the anchor or anchor rod has a threaded portion for receiving it. Other types of anchors are cone anchors, curved plates, which may be cast, or sheet metal, and other types of expanding anchors.

The cathode 14, which is shown in side elevation, locks the same whether it be made of tubular stock, as shown in Fig. 2, or solid cylindrical stock, as shown in Fig. 3.

In Fig. 2 the anode 14a comprises a tubular member of magnesium, having an inner threaded bore 19, the threads of which may extend all the way through the bore, or may terminate at a central point at which the threaded end of the guy rod becomes locked in the anode.

If threaded all the way through, the anode is locked by its engagement with the nut 13, with which it acts as a lock nut.

If desired, the anode 14b of Fig. 3 may be made of a magnesium casting, or tapped bar stock. In such case, the threaded bore 20 need extend into the solid anode 14b onlysufiiciently to permit it to be threaded tightly on the threaded end 12 of the guy rod.

Another form of anode is shown in Fig. 4, Where a magnesium plate or washer, which may be cast or made of sheet metal, is indicated at 21. This magnesium plate 21 has an unthreaded bore 22 and is engaged with the body 23 of the anchor by being located between the nut and the body of the anchor.

The pull of the guy rod 10 on the anchor body 23 keeps the magnesium plate 22 in conducting engagement with the anchor.

The operation of the present anodes is as follows: If an anode were buried in the ground at a point spaced from the anchor and connected by an electrical conductor, preferably insulated, to the guy rod and anchor, the anode would present a closer resemblance to a galvanic cell, like which it operates.

The intervening damp earth acts as an electrolyte; and the galvanic action of the electrolyte on the steel showing sheet or be used upon all types of.

magnesium anode and the anchorthroughthe surrounding earth; and the anchor is preferably coated with asphaltum paint.

The amount of current generated depends upon the size of the cathode and the area of the anchor to be protected, and usually amounts to approximately one milliampere per square foot of the anchor surface of the anchor to be protected. For example, with an anchor of average size, protection may be provided for many years by means of an anode of cylindrical shape, substantially six inches long and one and a half inches in diameter.

The external shape of the anodes may be varied; and those shown in Figs. 2 and 3 may be cylindrical because that enables the use of tubular stock and round stock.

The magnesium washer shown in Fig. 4 may be circular, if a casting; or, if made of Sheet metal, it may be rectangular to avoid waste.

Referring to Fig. 6, this is a view similar to Fig. 2, showing another form of anode in which the magnesium anode 30 may be substantially spherical or oval or egg shaped with a fiat end portion 31 for engaging the nut.

The amount of protection for the guy rod and anchor against corrosion and galvanic action depends on the volume of magnesium which is provided with a minimum amount of external surface; The greater the volume of magnesium, the longer the magnesium will last in a sphere having the greatest volume within a minimum surface area. Such an anode will last longer than anodes of other shape having the same mass.

It is estimated that in certain regions where there is alkaline soil and other regions where there is salty soil, the use of such anodes will increase the life of the guy rod and anchor as much as from a life of ten years without the anode to a life of eighteen years with the anode.

Referring to Fig. 5, this is a View similar to Fig. 1 of another type of installation, which is preferred on many power lines because of the additional grounding secured by using the guy cable and guy rod as a ground. In this figure, 32 indicates a line pole provided with a grounding wire 33 leading to a copper grounding rod 34 embedded in the earth, the free surface of which is indicated at 35.

The guy rod is indicated at 36 and provided with an anchor 37 engaged by a nut 38 and provided with a magnesium anode 39 of spherical shape, except for the upper fiat surface 31 engaging the nut. The guy rod eye 41 has a guy cable 42 secured to it by means of a cable clamp 43; and the upper end of the cable guy 42 has a loop 44 through an eye bolt 45, which passes through the pole and is secured by a nut 45.

The guy cable has the usual cable clamp 47; and grounding wire 33 is connected to the guy cable 42 by a jumper wire 48.

The insulator of Fig. 1 has been eliminated; and a closed circuit has been provided above ground. This facilitates galvanic action, in which the copper grounding rod is the positive element and the steel rod and anchor constitute a negative element with currents passing in the direction indicated by the arrows.

Where such an insulator between the guy cable and guy rod is eliminated, the need for cathodic protection is increased, but this form of installation is preferred where the users wish to improve their grounding system by using the guy as a ground. In either case, erosive improved protective apparatus mum amount of machining;

action on the guy rod and anchor is greatly reduced by the use of the present anodes.

The present anodes have the advantage that they do not require the digging of a separate hole or the connection of a separate insulated wire from guy rod to anode. They may be installed as a unit simultaneously with the anchor and guy rod; and this saves considerable labor.

Furthermore, the threaded connection for the location of a magnesium washer between the nut and the anchor body absolutely insures a good electrical connection, although installed by unskilled labor. 7

As the resistance in circuit may have a bearing on the amount of current generated by the cathodic action, the contact resistance between the anodes of Figs. 2 and 3 and the guy rod may be regulated by the amount of threaded engagement; and this may be done by regulating the location of the nut on the threaded portion 12 of theguy rod, so'that there is only a suitable amount of threaded engagement for any particular installation.

An insulating connection between the guy cable 24 and the guy rod is preferred in the anchoring system and is believed will result in considerably increased anode life. The theory for such an insulator may be that it avoids the action of other EMFs that might be generated in the circuit and transmitted to the guy rod.

For this purpose the installation may include insulator 25, engaging the loop of guy rod cable 24 and a separate cable or metal loop 26, connecting the eye 11 and the eye of the insulator 25. Other installations such as that shown in'Fig. 5 may omit the insulating connection.

Itwill thus be observed that I have invented an for protecting guy rods and anchors against corrosion by galvanic action. My anodes are simple in construction and involve a miniandthey may be manufactured very cheaply and 'nstalled with a minimum amount of labor as apart of the anchor and guy rod installation. The amount of resistance between the guy rod and the anode maybe adjusted by means of the threaded connection.

The present magnesium anodes are of particular benefit where the installation includes a copper grounding rod connected electrically to the guy cable, which is electrically connected tothe guy rod and anchor. In such cases thereis a great need for cathodic protection by the use of anodes of magnesium; and the most eilicient protection'may'be provided by an installation as shown .in Fig. 5.

While I have illustrated a preferred embodiment of my invention, many modifications may be made without departing from the spirit of the invention, and I do not wish tobe limited tothe precise details of construction setforth, but desireto avail myself of all changes within the scope of the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States, is:

1. A protective assembly for reducing erosion of guy rods and anchors by galvanic action for a guy rod and anchor employed with a line pole comprising a steel guy rod having an eye at its upper end, a guy cable having a loop in said eye and having the end of the cable secured by a cable clamp, an eye bolt passing through a line pole and having an eye at its end, a loop in the other end of said cable secured in said eye by a cable clamp, a steel earth anchor carried by the lower end of the guy rod, said rod having its upper end projecting from the earth and having its lower end passing through an aperture in the earth anchor, with said lower end and anchor embedded in the earth and subject to galvanic action of the earth and bodies in the earth, said rod having a nut on'its lower end engaging the lower side of the earth anchor, and said rod being installed under tension resisted by said anchor, said rod having its threaded end projecting downwardly below said nut, and having a round magnesium anode provided with a threaded bore threaded on the projecting threaded end of said rod and installed in the earth in the same hole, a ground rod in the earth adjacent said pole and having a ground wire connected thereto and attached to said pole, and a conductor connecting said guy cable to said ground wire.

2. A protective assembly for reducing erosion of guy rods and anchors by galvanic action, comprising a steel guy rod having an eye at its upper end and a threaded portion at its lower end, a metal closed loop passing through said eye and through an insulator having a transverse eye for said loop, a guy cable secured to said insulator by passing through said insulator inside said loop, an earth anchor carried by the threaded end of said guy rod and adapted to be embedded in the earth,

a threaded member on said threaded end below said 20 anchor, and an anode of magnesium having a threaded bore complementary to said threaded portion, said anode being threaded home on said threaded portion and into engagement with said threaded member, thereby placing a contacting pressure on the threads of said rod and said anode to produce a good electrical contact between said guy rod and anchor and said anode.

References Cited in the file of this patent UNITED STATES PATENTS Re. 4,048 Lighthall June 28, 1870 Re. 23,036 Tallman Aug. 31, 1948 2,157,180 Little May 9, 1939 2,401,546 Brown June 4, 1946 2,466,239 Holcombe Apr. 5, 1949 2,478,478 Grebe Aug. 9, 1949 OTHER REFERENCES Status of Cathodic Protection Lines in 1941, by Logan, pages 5 and 6. 

1. A PROTECTIVE ASSEMBLY FOR REDUCING EROSION OF GUY RODS AND ANCHORS BY GALVANIC ACTION FOR A GUY ROD AND ANCHOR EMPLOYED WITH A LINE POLE COMPRISING A STEEL GUY ROD HAVING AN EYE AT ITS UPPER END, A GUY CABLE HAVING A LOOP IN SAID EYE AND HAVING THE END OF THE CABLE SECURED BY A CABLE CLAMP, AN EYE BOLT PASSING THROUGH A LINE POLE AND HAVING AN EYE AT ITS END, A LOOP IN THE OTHER END OF SAID CABLE SECURED IN SAID EYE BY A CABLE CLAMP, A STEEL EARTH ANCHOR CARRIED BY THE LOWER END OF THE GUY ROD, SAID ROD HAVING ITS UPPER END PROJECTING FROM THE EARTH ANCHOR, WITH SAID LOWER END AN APERTURE IN THE EARTH ANCHOR, WITH SAID LOWER END AND ANCHOR EMBEDDED IN THE EARTH AND SUBJECT TO GALVANIC ACTION OF THE EARTH AND BODIES IN THE EARTH, SAID ROD HAVING A NUT ON ITS LOWER END ENGAGING THE LOWER SIDE OF THE EARTH ANCHOR, AND SAID ROD BEING INSTALLED UNDER TENSION RESISTED BY SAID ANCHOR, SAID ROD HAVING ITS THREADED END PROJECTING DOWNWARDLY BELOW SAID NUT, AND HAVING A ROUND MAGNESIUM ANODE PROVIDED WITH A THREADED BORE THREADED ON THE PROJECTING THREADED END OF SAID ROD AND INSTALLED IN THE EARTH IN THE SAME HOLE, A GROUND ROD IN THE EARTH ADJACENT SAID POLE AND HAVING A GROUND WIRE CONNECTED THERETO AND ATTACHED TO SAID POLE, AND A CONDUCTOR CONNECTING SAID GUY CABLE TO SAID GROUND WIRE. 